Loans (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	$ 2,031	$ 729
60-89 Days Past Due	184	7
Greater Than 90 Days Past Due	3,686	4,092
Total Past Due	5,901	4,828
Current	478,927	496,574
Total Financing Receivables	484,828	501,402
Recorded Investment > 90 Days and Accruing	3	1
Consumer real estate [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	613	575
Greater Than 90 Days Past Due	310	648
Total Past Due	923	1,223
Current	76,237	79,064
Total Financing Receivables	77,160	80,287
Recorded Investment > 90 Days and Accruing
Agricultural Real Estate [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
Current	35,898	40,143
Total Financing Receivables	35,898	40,143
Recorded Investment > 90 Days and Accruing
Agricultural [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	9	11
Total Past Due	9	11
Current	51,887	57,759
Total Financing Receivables	51,896	57,770
Recorded Investment > 90 Days and Accruing
Commercial Real Estate [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	1,228
60-89 Days Past Due	139
Greater Than 90 Days Past Due	845	877
Total Past Due	2,212	877
Current	207,389	199,122
Total Financing Receivables	209,601	199,999
Recorded Investment > 90 Days and Accruing
Commercial and Industrial [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	154	78
60-89 Days Past Due	27
Greater Than 90 Days Past Due	2,528	2,567
Total Past Due	2,709	2,645
Current	88,272	100,278
Total Financing Receivables	90,981	102,923
Recorded Investment > 90 Days and Accruing
Consumer [Member]
Contractual aging of the recorded investment in past due loans by portfolio segment of loans
30-59 Days Past Due	27	65
60-89 Days Past Due	18	7
Greater Than 90 Days Past Due	3
Total Past Due	48	72
Current	19,244	20,208
Total Financing Receivables	19,292	20,280
Recorded Investment > 90 Days and Accruing	$ 3	$ 1

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Financing receivables current and past due.

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5111-111524

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Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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